Half to charles v



,.UNITED STATES "tif l PAfiEN-T OFFICE..

JOSEPH c. STEEER, OE SANIEEANOISOO, onLiEoENm, ASSIGNOE OE ONE.-

HALE To CHARLES vMANNER, OE SAME PLACE.

f v,SCREW-Tiwy SPECIFICATION forming part of `Letters Patent No. 284,5 1, dated September 4, 1883.

Applicatioii filed September 20, 18E-2. (No model.)

` Afor Boiler-Makers, of which the following isa specification. y

This invention relates to that class of bolttaps which are used by boiler-makers `for the purpose of threading holes in boilers for the reception of stay-bolts.

In the drawings which arehereuntoannexed,

l and which form a part of this specification,

. sleeve.

Figure l is a side elevation of my improved stay-bolt tap. Fig. 2 is a central longitudinal section. Fig. 3 is a top view of the threaded Fig. 4 is a side view illustrating a modication of the threaded sleeve, and Fig. 5 is a sectional plan `view of the same.

Similar letters of reference are used `to indicate like parts throughout the several Views. `A represents the stem ofthe reanier or tap, uponwhich is placedthe sleeve B. rlhe sleeve is bored smooth, `and is adapted to be freely moved up and down upon the stem A, and the lower portion thereof is provided with a screwthread, C, which is of the same diameter as the threaded bolt-hole cut by the reamer D. `The upper part ofthe sleeve is made thicker or of `greater diameter than the threaded portion, and it is pierced at its upper end for the reception of the headed pin or bolt E, which enters one of a series of holes, F, formed in the tap-stem. y

`At a point about midway of the lengthof -the sleeve I pivot, by means of the screw-bolt G, the swinging arm H. Ihe said bolt G also holds in place the spring-plate I, which is slotted at its upper or outer end, so as to embrace the pin E. r

It should here be remarked that the lower end J of the pivoted arm H is to be somewhat pointed and rounded off, "and that the upper end K is `made beveled or concave in the direction of its width, the lowest .point or edge being on a diametrical line with the inner end or pointJ. rIhe object in thus con-` structing thelever-arm will be more fully described hereinafter.

A small stop or pin, L,` placed at one side turned so as to uncover the head of the pin E and a small lug may be formed on the under side of the lowest edge of the lever end K,

` of the arm H, prevents the arm from being I Whichwill prevent said arm from being moved i overl and beyond the pin E aftersaid piu has been forced home into the hole F.

In the modification shown in Figs. and 5 I dispense with the tripping mechanism hereinbefore described and makethe upper portion of the sleeve B of less diameter than the screwthreaded portion C, and set the said sleeveat the proper distance from the tap by means of a small screw, Z, which enters the holes F in the tap-stem A. ,'Rotation of the stem within the sleeve is prevented by the key or gib Y, which enters a keyway cut lengthwise in the stem A and rmly keys or binds the two together, and for every turn the tap makes in the lower plat'e the sleeve will also make one in the upper plate.

For the purpose of withdrawing the tool it before the threads of the sleeve B engage with the threads of the upper bolt-hole, and the said sleeve is held in this position by the pin E entering one of the holes F, and in which it is kept by the lower edge of the raised or concave end K of the arm H pressing upon its head, as seen in Figs. 1 and 2. Thetap isthen screwed through the outer shell of the boiler; but before the threads of the tap take hold of the metal of the inner shell or casingthethreaded' end of the sleeveBwill have entered the taphole in the outer casing, and the rotation ofthe tap-stem will cause the said sleeve to beturned down into the threaded hole until the point J of the arm H comes in contact with the outer face of the boiler, when it will be tripped or partially rotated upon its pivotal point sufficiently far to release its upperl end, K, from close Contact with the pin E, when the spring tial entrance of the tap into the lower bolt-hole IOO I, by pressing upon the under side of the pin- Y of the free revolution of said stem within the hole F and permit the free rotation of the tapstem within the sleeveWhieh serves to eenf ter the stem`Y and prevents abrasion of the threads in thetap-'hole ofthe outer boiler-plate.

Having th us'd'eseribed my invention, what I claim, and desire to secure by Letters Patent,A 1s- 1. In combination with atap for making stay- -bolt holes in steam-boilers, and other like purposes, an adjustable sleeve secured upon the stem of such screw-tap and provided With a screw-thread of like diameter to that made by the tap, and having an automatic tripping device, whereby the sleeve may be released from positive Contact With the tap-stem and permit sleeve, substantially in the manner asvk herein set forth and specified.

2. The combination, with the tap and tapstem A, having` a series of perforations, F F, of the sleeve B, having a male thread, C, and a pivoted lever-arm, H, movable pin or bolt E, and spring I, constructed, arranged, and operating substantially in the manner and for the purpose herein set forth and specified. Y

In testimony that I Vclaim the foregoing I have hereunto set my hand and seal this 2d day of September, 1882.

' JOSEPH C. STEBER. [L s] Witnesses:

C. W. M. SMITH, WILMER BRADFORD. 

